SOLUTION: Dear Tutor, Brigit is 8 years older than Andrew. In twenty years, the sum of their ages will be 128. How old are they now? *Can I set the equation up this way?: 8x+20=128

Question 1023394: Dear Tutor,
Brigit is 8 years older than Andrew. In twenty years, the sum of their ages will be 128. How old are they now?
*Can I set the equation up this way?: 8x+20=128 and solve for x? When I do solve, I get: x=13.5
To check, I put 13.5 in for the previous equation and it made sense since both sides of the equation were the same. Tutor, am I doing this right? Please let me know and thank you in advance!
Answer by josgarithmetic(39616) (Show Source): You can put this solution on YOUR website!
Literally translate the description into number statements.

x, Brigit
y, Andrew

--
Assign variables to unknown quantities. Brigit's age and Andrew's age are unknown and these were then assigned. Use these variable assignments to translate the description of the problem literally, into equations.

The equations are formed to account for the age relation between Andrew and Brigit "now" and to account for that relation in some unknown x years in the future, and this equation-based accounting comes LITERALLY from the description.

Next, SOLVE the system of equations. DO YOU KNOW HOW TO SOLVE THAT SYSTEM OF EQUATIONS?
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